Chemical Species Profiles of Laminar propane-Air Flames

Abstract

The mole fractions of all CI-C4 hydrocarbons, CO, C02, Nz, and Oz have beenmeasured through the luminous zone and into the post-flame gases of laminar propane-airflames at one atmosphere pressure. The experiments were performed on a flat-flame burner, andsamples were withdrawn by an uncooled quartz probe for gas chromatographic analysis. Measure-ment of the perturbation of the species distributions by the probe sampling technique have beencarried out where possible. Concentration-distance profiles have been obtained at three fuel-airequivalence ratios (0.63, 1.0, and 1.46) and at two flame temperatures (1680 and 1880°K) for thefuel-rich equivalence ratio. These results are compared with predicted concentrations obtainedby flame model calculations which include extensive chemical reaction mechanism sets. Thereare deviations of up to a factor of 10 between the predicted and the measured concentrations ofcertain species. These measurements provide crucial data from which better reaction mechanismsand rate constants can be derived.